The boys hoped to catch a glimpse of a diamond. The ground had all been squared off into different claims--which had cut it up into blocks, cubes and rectangles. Each claim had its own wires and trollies bringing up the precious "blue" to the surface. As the countless tubes of the aerial tramway glided rapidly back and forth--upwards and downwards through the labyrinthine network of wire-rope stretching over the sides of the mine--the vast abyss seemed filled with flights of birds fluttering to and fro. "Uncle Abraham told me the story about the finding of the first rough gem here," said Petrus to George. "The children of a Dutch farmer had a small soapy-appearing stone for a plaything. They thought it was nothing but a pebble. But a visitor noticed the strange stone one day and offered to buy it. The mother laughed and gave it to him gladly. Then it was examined by many experts and pronounced a valuable diamond." "That was the beginning of one of the greatest industries the world has ever known," added the lieutenant. "Then from the 'Premier Mine,' near Pretoria, was taken the great 'Cullinan diamond,' which weighed a pound and a half. That was the most valuable diamond ever found, its value being $2,500,000." "And it was called the 'Star of Africa,' and presented to King Edward, wasn't it, Daddy?" exclaimed George. "Yes, George. And part of it is set in His Majesty's scepter and part in his crown," explained the lieutenant, as they were bobbing along in the same old vehicle through the sand and dirt and wind-storm for their train. Soon they were whirling towards Cape Town. For nearly two nights and days the train continued on its way over vast stretches of arid plains. Only a few small, dried-up, lavender-colored "Karroo" bushes here and there were seen, with now and then a flat-topped kopje. They were crossing the "Great Karroo"--a region of limitless sky and sand. Desolation marked every mile of the way. "It's just like that Kalahari Desert, Father! Some of it has gotten inside this car, too!" protested George. A fine white alkaline powder had penetrated the car, sifted into their baggage, down their collars, into their eyes, hair, and everywhere it should not be. Even the food tasted gritty. All the next day they were still passing over the same great burning waste of sandy, sun-swept veldt. "'Karroo' is a Hottentot name, meaning dry or barren," Petrus explained. Even the river-beds were dried up. Towards evening, when a sudden hard rain fell over the dry tussocky grass, the effect was magical. Hundreds of wild flowers burst suddenly into bloom, glowing brightly in the wilderness. The boys' excitement in watching for the possible appearance of elephants and giraffes on the "Karroo" was giving way to doubt as none appeared. Petrus had read of as many as five hundred giraffes in one herd.